Molecular cloning and mapping of 10 new probes on the human Y chromosome.

We have developed a novel positive cloning vector whose use precludes the cloning of any fragments less than 0.8 kb as well as 3.4-kb EcoRI fragments of DYZ1, the largest repeating-DNA family on the long arm of the human Y chromosome. Using this vector, we subcloned inserts of a Y-chromosome-specific phage library constructed from EcoRI-digested flow-sorted Y-chromosome DNA. Ten novel Y-specific fragments were obtained. Their localization on the Y chromosome was determined by deletion mapping using clinical samples with structurally abnormal Y chromosomes. The long arm of the Y chromosome was divided into 12 segments by the novel probes in combination with established probes. The amelogenin-like sequence, mapped on the long arm in Human Gene Mapping 10, has been mapped on the short arm.